Electric hair cutting appliances come in a number of different types depending on the intended use of the appliance, such as for trimming facial or body hair, clipping the hair on one's head or on a pet, or for shaving facial or body hair. Such hair cutting appliances typically have at least one stationary blade and at least one reciprocating blade. Each of the blades includes a plurality of shearing teeth defining a cutting edge margin. The shearing teeth of the reciprocating blade overlie, in face-to-face contact with, the shearing teeth of the stationary blade. The reciprocating blade is operatively connected to an eccentric drive assembly such that rotation of the drive assembly linearly reciprocates the reciprocating blade relative to the stationary blade so that the shearing teeth of the reciprocating blade reciprocate across the shearing teeth of the stationary blade, thereby producing shearing action between the reciprocating blade teeth and the stationary blade teeth.
Some hair cutting appliances include at least one comb, also known as a guard. The comb includes a plurality of teeth that are positioned generally adjacent to the cutting edge margin of the hair cutting appliance. In use, the hair cutting appliance is positioned so that the comb is in contact with the subject's skin, and the hair cutting appliance is moved relative to the hair so that the comb remains in contact with the subject's skin. As the hair cutting appliance is moved, the comb directs the hair toward the cutting edge margin of the hair cutting appliance. The comb is configured to maintain the cutting edge margin of the hair cutting appliance at a selected distance from the subject's skin so that the comb, in effect, regulates the length of hair cut by the hair cutting appliance to facilitate cutting the hair to a desired length.
In one example of a hair cutting appliance, a plurality of interchangeable combs are provided to allow hair to be cut to different haircut lengths. In effect, each comb corresponds to one of a variety of different haircut lengths. Each comb is removably and repeatedly attachable to the hair cutting appliance. Thus, in this type of hair cutting appliance, the user must chose a haircut length from a plurality of discrete, preselected haircut lengths, and then the user must locate the appropriate comb that corresponds to the selected haircut length and attach the selected comb to the hair cutting appliance.
In another example, the comb is adjustable to different haircut length positions such that a single comb facilitates cutting hair to different haircut lengths. In such an example, the comb is selectively movable, relative to the cutting edge margin of the hair cutting appliance, to a discrete, preselected number of haircut length positions to facilitate cutting hair to a discrete, preselected number of haircut lengths. The user can only cut hair to one of these discrete, preselected haircut lengths. Thus, the functionality of the hair cutting appliance is inherently limiting, much like the type of hair cutting appliance that includes a plurality of different combs.